1. Field of the Invention
This invention relates to an antenna device, more particularly to an ultra wide bandwidth (UWB) antenna device formed with imaginary slots in a dielectric substrate thereof.
2. Description of the Related Art
Use of ultra wide bandwidth (UWB) in wireless personal area network (WPAN) is the current trend. FIGS. 1 and 2 respectively illustrate a conventional inverted-F antenna 1 and a conventional slot antenna 2, which cannot be operated at the UWB range. FIG. 3 illustrates another conventional antenna that includes a radiating element 11 and a ground element 12, and that can be operated at the UWB range. The conventional UWB antenna is disadvantageous in that the radiating element 11 is perpendicular to the ground element 12 and that the area of the ground element 12 (10 cm×10 cm) is relatively large. As such, it is relatively difficult and inconvenient to integrate the conventional UWB antenna into a circuit board.
There is a need to provide an antenna that is capable of operating at the UWB range, that can be easily manufactured, and that can be miniaturized.